Fabric pretreatment for inkjet printing

ABSTRACT

This invention pertains to inkjet printing on fabric and to a pretreatment solution for the fabric that allows high quality printing thereon. The aqueous pretreatment solution/emulsion comprises a nonionic latex polymer and a multivalent cationic salt.

BACKGROUND OF THE INVENTION

This invention pertains to inkjet printing on a pretreated fabric withcolored inkjet inks, and to a pretreatment solution for the fabric thatallows high quality printing thereon.

Digital printing methods such as inkjet printing are becomingincreasingly important for the printing of textiles and offer a numberof potential benefits over conventional printing methods such as screenprinting. Digital printing eliminates the set up expense associated withscreen preparation and can potentially enable cost effective short runproduction. Inkjet printing furthermore allows visual effects such astonal gradients and infinite pattern repeat sizes that cannot bepractically achieved with a screen printing process.

While digital printing provides a breadth of available printingconditions for almost any fabric, there is often a need for achieving ahigher color on the fabric. It is an object of this invention to enablehigher color, high quality inkjet printing of fabrics, such as cottonand cotton blends, with colored inkjet inks.

SUMMARY OF THE INVENTION

In one aspect, the present invention relates to a method of digitallyprinting a textile comprising the steps of:

-   -   (a) pretreating the textile with an aqueous pretreatment        solution comprising a nonionic latex polymer and a multivalent        cationic salt solution,    -   (b) digitally printing the dried, pretreated textile with a        colored ink jet ink,    -   where the nonionic latex polymer has sufficient nonionic        components such that the nonionic latex polymer is stable in the        presence of the multivalent cationic salt solution.

The present invention pertains, in another aspect, to a fabric that hasbeen pretreated with an aqueous mixture of nonionic latex polymer and amultivalent cationic salt solution, wherein the multivalent cationicsalt is a calcium salt selected from the group consisting of calciumnitrate, calcium nitrate hydrate, calcium chloride, calcium chloridehydrate and mixtures thereof.

These and other features and advantages of the present invention will bemore readily understood by those of ordinary skill in the art from areading of the following detailed description. It is to be appreciatedthat certain features of the invention which are, for clarity, describedabove and below in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention that are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany subcombination. In addition, references to in the singular may alsoinclude the plural (for example, “a” and “an” may refer to one, or oneor more) unless the context specifically states otherwise.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Pretreatment Solution

The aqueous pretreatment solution used in the method of the presentinvention is a nonionic latex polymer and a multivalent cationic saltsolution. More preferably, the preteatment solution comprises a solutionof a nonionic latex polymer and a multivalent cationic salt in water. Byaqueous pretreatment solution it is understood that the nonionic latexpolymer may be present as a stable emulsion in the pretreatmentsolution. Optionally, other ingredients can be added. Ingredientpercentages mentioned hereinafter are weight percent based on the totalweight of the final solution, unless otherwise indicated.

Nonionic Latex Polymer

The pretreatments for the particular textile substrates, include anonionic latex polymer in order to further enhance the adhesion and/orwashfastness of ink colorants on the textile fabric substrates. It hasbeen found that pretreated textiles including a nonionic latex polymerprovide high color density and saturation relative to untreatedtextiles, superior print quality relative to untreated textiles,reduction of wicking or bleeding relative to untreated textiles, andenhanced ink absorption relative to untreated textiles. Furthermore, thepretreatment formulations provide a washfast printed image when printingvia an ink jet printing process. By way of example only, the nonionicmaterials may include urethanes, vinylacetate, ethylene-vinylacetate,acrylate, acrylamide, styrene, and styrene-acrylate resins and othernonionic latexes. One or more nonionic latex polymers may be used in thepretreatment solution.

The preferred use of the nonionic latex polymer is that it is added tothe multivalent cationic salt solution. The nonionic latexpolymer/multivalent cationic salt solution must be stable as a solutionor as a stable emulsion to permit the treatment of the fabric. If thenonionic latex polymer gels, or its emulsion is not stable in thepresence of the multivalent cationic salt solution, than it cannot beused as a pretreatment additive. A screening test for whether a nonioniclatex polymer is stable in the presence of the multivalent cationic saltsolution is to mix a 10 wt % polymer (on a dry basis) and a 15 wt % ofcalcium nitrate tetrahydrate and observe whether the solution/emulsionis stable. The stability observations at ambient temperature (˜25°) andat 10 minutes and 24 hours. The nonionic component must lead to a stablenonionic latex polymer/multivalent cationic solution/emulsion

The nonionic latex polymer can be utilized as a separate pretreatmentsolution or combined with the multivalent cationic solution describedabove. A common solution for the nonionic latex polymer and themultivalent cationic salt is preferred.

The nonionic component of the latex polymer can come from theincorporation of a nonionic reactant into the latex polymer. Examples ofnonionic components include, ethylene oxide derivatives, acrylamide,hydroxyethyl-substituted monomers, vinylpyrrolidone, ethyleneimines andthe like. The incorporation can occur during the polymerization step, orbefore after the polymerization step which prepares the latex polymer.In the case of an ethylene oxide nonionic component, the substitutioncan take the form of incorporating a glycol with sufficient(—CH₂—CH₂O—)_(n) units to impart the nonionic stability. For instance, apolyurethane may have an alkyl polyethylene glycol incorporated into thenonionic polyurethane. The nonionic component can be the main componentin nonionic latex polymer, as long as its properties satisfy thestability test described above.

The nonionic latex polymer may also have ionic components incorporatedinto the polymer. By example, for the polyurethanes ionic componentssuch as acids may be used in the polyurethane reaction and a specificacid example is dimethylolpropionic acid. For the acylamide andhydroxyethyl substituted nonionic latex polymer the ionic source can befrom (meth)acrylic acids. There are limits to the amount of ioniccomponents in the nonionic latex polymer, since the nonionic componentsmay complex with the multivalent cationic and form complex that willlead to instability of the nonionic latex polymer/multivalent cationicsolution. The balance of nonionic and ionic components must lead to astable solution as described above.

By example, in the case of a polyurethane nonionic latex polymer thenonionic content must be at least about 15 milliequivalents/gram ofethylene oxide units incorporated into the polyurethane, or in the caseof the polyurethane preferably at least about 25 milliequivalents/gramwhere the milliequivalent/gram calculation is based on the dry polymerweight. In the polyurethane nonionic latex polymer the ionic componentcan be less than about 10 milliequivalents/gram.

The solution should comprise sufficient nonionic latex polymer contentand other ingredients to provide adequate infusion and/or coating of thetextile with the nonionic latex polymer. Typically, the pretreatmentwill comprise at least about 0.5 wt % of the nonionic latex polymer, andamounts can be used up to the solution/emulsion stability of theparticularly nonionic latex polymer utilized. Preferably, thepretreatment will comprise from about 1 wt % to about 24 wt % of thenonionic latex polymer.

Multivalent Cation

The pretreatments of this invention comprise one or more multivalentcations. The effective amounts needed in a particular situation canvary, and some adjustment, as provided for herein, will generally benecessary.

“Multivalent” indicates an oxidation state of two or more and, for anelement “Z”, are typically described as Z²⁺, Z³⁺, Z⁴⁺ and so forth. Forbrevity, multivalent cations may be referred to herein as Z^(x). Themultivalent cations are substantially soluble in the aqueouspretreatment solution and preferably exist (in solution) in asubstantially ionized state so that they are in a form where they arefree and available to interact with textile when the textile is exposedto the pretreatment solution.

Z^(x) includes, but is not limited to multivalent cations of thefollowing elements: Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr, V, Cr, Mn, Fe,Ru, Co, Rh, Ni, Pd, Pt, Cu, Au, Zn, Al, Ga, In, Sb, Bi, Ge, Sn, Pb. Inanother embodiment, the multivalent cation comprises at least one of Ca,Ba, Ru, Co, Zn and Ga. In yet another embodiment, the multivalent cationcomprises at least one of Ca, Ba, Ru, Co, Zn and Ga. Preferably themultivalent cation is Ca.

Z^(x) can be incorporated into pretreatment solution by addition in asalt form or by addition in an alkaline form and used as a base in theadjustment of the pretreatment solution pH.

The associated anionic material can be chosen from any common anionicmaterial, especially halides, nitrates and sulfates. The anionic form ischosen so that the multivalent cation is soluble in the aqueouspretreatment solution. The multivalent cationic salts can be used intheir hydrated form. One or more multivalent cationic salts may be usedin the pretreatment solution.

For Ca, the preferred multivalent cation salts are calcium chloride,calcium nitrate, calcium nitrate hydrate and mixtures thereof.

Other optional ingredients in the pretreatment solution may include, butare not limited to, humectants and biocides. Biocides prevent microbialdegradation—their selection and use is generally well known in the art.Suitable humectants are the same as those suitable for use in coloredinkjet inks, as discussed in further detail below.

The balance of the pretreatment solution is water. A pretreatmentsolution consisting essentially of a nonionic latex polymer and amultivalent cationic salt in water is particularly suitable.

The solution should comprise sufficient multivalent cation content andother ingredients to provide adequate infusion and/or coating of thetextile with the multivalent cation. Typically, the pretreatment willcomprise at least about 0.5 wt % of the multivalent cation salt, andamounts can be used up to the solubility limits of the particularlymultivalent cation salt or salts utilized. Preferably, the pretreatmentwill comprise from about 1 wt % to about 30 wt % of the multivalentcation salt. The combined total weight of the nonionic latex polymer andthe multivalent cation salt can be up to about 45 wt %.

Fabric

The fabric to be pretreated can be any fabric suitable for printing withcolored inkjet inks, and is preferably a fabric comprising cotton and/orcotton blends.

Pretreatment of the Fabric

Application of the pretreatment to the fabric can be any convenientmethod and such methods are generally well-known in the art. One exampleis an application method referred to as padding. In padding, a fabric isdipped in the pretreatment solution, then the saturated fabric is passedthrough nip rollers that squeeze out the excess solution. The amount ofsolution retained in the fabric can be regulated by the nip pressureapplied by the rollers. Other pretreatment techniques include sprayapplication wherein the solution is applied by spraying on the face orface and back of the fabric. Spraying can be limited to the digitallyprinted area of the printed fabric. An example of where this limitedspraying would be particularly applicable is in the digital printing ofan image on preformed textile articles such as, for example, a T-shirts,caps, undergarments and like clothing articles.

Preferably, the pretreatment solution is applied to the fabric in a wetpick-up of from about 0.20 to about 7.5 grams of multivalent cationic(calcium) salt per 100 grams of fabric, more preferably from about 0.60to about 6.0 grams of multivalent cationic (calcium) salt per 100 gramsof fabric, and still more preferably from about 0.75 to about 5.0 gramsof multivalent cationic (calcium) salt per 100 grams of fabric.

After application of pretreatment, the fabric may be dried in anyconvenient manner. The fabric is preferably substantially dry at thetime of printing, such that the final percent moisture is(approximately) equal to the equilibrium moisture of the pretreatedfabric at ambient temperature. The absolute amount of moisture in thefabric, of course, can vary somewhat depending on the relative humidityof the surrounding air.

The nonionic latex polymer remaining in the fabric after drying providean interactive material that will interact with the inkjet inks duringprinting and improve the properties such washfastness of the printedtextile It will be appreciated that sufficient nonionic latex polymermust be present to effect a brighter/more colorful image. Routineoptimization will reveal appropriate nonionic polymer latex levels for agiven printer and colored ink or ink set.

The multivalent salts remaining in the fabric after drying provide aninteractive material that will interact with the inkjet inks duringprinting. It will be appreciated that sufficient multivalent salts mustbe present to effect a brighter/more colorful image. Routineoptimization will reveal appropriate multivalent salt levels for a givenprinter and colored ink or ink set.

Colored Inkjet Inks

The colorant used for printing the colored image may be a dye or apigment. Dyes include disperse dyes, reactive dyes, acid dyes and thelike. The colored inkjet inks and the white ink are preferably aqueousand do not contain components that are UV curable.

Pigmented inks are preferred. Pigmented inkjet inks suitable for use inthe present method typically comprise a pigment dispersed in a vehicle.Aqueous vehicles are preferred. Preferably, the pigment ink comprises ananionically stabilized pigment dispersed in an aqueous vehicle.

An “aqueous vehicle” refers to a vehicle comprised of water or a mixtureof water and at least one water-soluble organic solvent (co-solvent) orhumectant. Selection of a suitable mixture depends on requirements ofthe specific application, such as desired surface tension and viscosity,the selected colorant, and compatibility with substrate onto which theink will be printed.

Examples of water-soluble organic solvents and humectants include:alcohols, ketones, keto-alcohols, ethers and others, such asthiodiglycol, sulfolane, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinoneand caprolactam; glycols such as ethylene glycol, diethylene glycol,triethylene glycol, tetraethylene glycol, propylene glycol, dipropyleneglycol, tripropylene glycol, trimethylene glycol, butylene glycol andhexylene glycol; addition polymers of oxyethylene or oxypropylene suchas polyethylene glycol, polypropylene glycol and the like; triols suchas glycerol and 1,2,6-hexanetriol; lower alkyl ethers of polyhydricalcohols, such as ethylene glycol monomethyl ether, ethylene glycolmonoethyl ether, diethylene glycol monomethyl, diethylene glycolmonoethyl ether; lower dialkyl ethers of polyhydric alcohols, such asdiethylene glycol dimethyl or diethyl ether; urea and substituted ureas.

An aqueous vehicle will typically contain about 30% to about 95% waterwith the balance (i.e., about 70% to about 5%) being the water-solublesolvent. Ink compositions typically contain about 60% to about 95%water, based on the total weight of the aqueous vehicle.

Pigments suitable for being used with the multivalent pretreatment ofthe textile are those generally well-known in the art for aqueous inkjetinks. Traditionally, pigments are stabilized by dispersing agents, suchas polymeric dispersants or surfactants, to produce a stable dispersionof the pigment in the vehicle. More recently though, so-called“self-dispersible” or “self-dispersing” pigments (hereafter “SDP”) havebeen developed. As the name would imply, SDPs are dispersible in waterwithout dispersants. Dispersed dyes are also considered pigments as theyare insoluble in the aqueous inks used herein.

The dispersant or surface treatment applied to the pigment creates ananionic surface charge (“anionic pigment dispersion”). Preferably, thatsurface charge is imparted predominately by ionizable carboxylic acid(carboxylate) groups.

The pigments which are stabilized by added dispersing agents may beprepared by methods known in the art. It is generally desirable to makethe stabilized pigment in a concentrated form. The stabilized pigment isfirst prepared by premixing the selected pigment(s) and polymericdispersant(s) in an aqueous carrier medium (such as water and,optionally, a water-miscible solvent), and then dispersing ordeflocculating the pigment. The dispersing step may be accomplished in a2-roll mill, media mill, a horizontal mini mill, a ball mill, anattritor, or by passing the mixture through a plurality of nozzleswithin a liquid jet interaction chamber at a liquid pressure of at least5,000 psi to produce a uniform dispersion of the pigment particles inthe aqueous carrier medium (microfluidizer). Alternatively, theconcentrates may be prepared by dry milling the polymeric dispersant andthe pigment under pressure. The media for the media mill is chosen fromcommonly available media, including zirconia, YTZ and nylon. Thesevarious dispersion processes are in a general sense well known in theart, as exemplified by U.S. Pat. No. 5,022,592, U.S. Pat. No. 5,026,427,U.S. Pat. No. 5,310,778, U.S. Pat. No. 5,891,231, U.S. Pat. No.5,976,232 and US20030089277. The disclosures of each of thesepublications are incorporated by reference herein for all purposes as iffully set forth. Preferred are 2-roll mill, media mill, and by passingthe mixture through a plurality of nozzles within a liquid jetinteraction chamber at a liquid pressure of at least 5,000 psi.

After the milling process is complete the pigment concentrate may be“let down” into an aqueous system. “Let down” refers to the dilution ofthe concentrate with mixing or dispersing, the intensity of themixing/dispersing normally being determined by trial and error usingroutine methodology, and often being dependent on the combination of thepolymeric dispersant, solvent and pigment.

The dispersant used to stabilize the pigment is preferably a polymericdispersant. Either structured or random polymers may be used, althoughstructured polymers are preferred for use as dispersants for reasonswell known in the art. The term “structured polymer” means polymershaving a block, branched or graft structure. Examples of structuredpolymers include AB or BAB block copolymers such as disclosed in U.S.Pat. No. 5,085,698; ABC block copolymers such as disclosed inEP-A-0556649; and graft polymers such as disclosed in U.S. Pat. No.5,231,131. Other polymeric dispersants that can be used are described,for example, in U.S. Pat. No. 6,117,921, U.S. Pat. No. 6,262,152, U.S.Pat. No. 6,306,994 and U.S. Pat. No. 6,433,117. The disclosure of eachof these publications is incorporated herein by reference for allpurposes as if fully set forth.

Polymer dispersants suitable for use in the present invention compriseboth hydrophobic and hydrophilic monomers. Some examples of hydrophobicmonomers used in random polymers are methyl methacrylate, n-butylmethacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate,2-phenylethyl methacrylate and the corresponding acrylates. Examples ofhydrophilic monomers are methacrylic acid, acrylic acid,dimethylaminoethyl(meth)acrylate and salts thereof. Also quaternarysalts of dimethylaminoethyl(meth)acrylate may be employed.

A wide variety of organic and inorganic pigments, alone or incombination, may be selected to make the ink. The term “pigment” as usedherein means an insoluble colorant. The pigment particles aresufficiently small to permit free flow of the ink through the inkjetprinting device, especially at the ejecting nozzles that usually have adiameter ranging from about 10 micron to about 50 micron. The particlesize also has an influence on the pigment dispersion stability, which iscritical throughout the life of the ink. Brownian motion of minuteparticles will help prevent the particles from flocculation. It is alsodesirable to use small particles for maximum color strength and gloss.The range of useful particle size is typically about 0.005 micron toabout 15 micron. Preferably, the pigment particle size should range fromabout 0.005 to about 5 micron and, most preferably, from about 0.005 toabout 1 micron. The average particle size as measured by dynamic lightscattering is less than about 500 nm, preferably less than about 300 nm.

The selected pigment(s) may be used in dry or wet form. For example,pigments are usually manufactured in aqueous media and the resultingpigment is obtained as water-wet presscake. In presscake form, thepigment is not agglomerated to the extent that it is in dry form. Thus,pigments in water-wet presscake form do not require as muchdeflocculation in the process of preparing the inks as pigments in dryform. Representative commercial dry pigments are listed in previouslyincorporated U.S. Pat. No. 5,085,698.

In the case of organic pigments, the ink may contain up to approximately30%, preferably about 0.1 to about 25%, and more preferably about 0.25to about 10%, pigment by weight based on the total ink weight. If aninorganic pigment is selected, the ink will tend to contain higherweight percentages of pigment than with comparable inks employingorganic pigment, and may be as high as about 75% in some cases, sinceinorganic pigments generally have higher specific gravities than organicpigments.

Self-dispersed pigments can be used and are often advantageous overtraditional dispersant stabilized pigments from the standpoint ofgreater stability and lower viscosity at the same pigment loading. Thiscan provide greater formulation latitude in final ink.

SDPs, and particularly self-dispersing carbon black pigments, aredisclosed in, for example, U.S. Pat. No. 2,439,442, U.S. Pat. No.3,023,118, U.S. Pat. No. 3,279,935 and U.S. Pat. No. 3,347,632.Additional disclosures of SDPs, methods of making SDPs and/or aqueousinkjet inks formulated with SDP's can be found in, for example, U.S.Pat. No. 5,554,739, U.S. Pat. No. 5,571,311, U.S. Pat. No. 5,609,671,U.S. Pat. No. 5,672,198, U.S. Pat. No. 5,698,016, U.S. Pat. No.5,707,432, U.S. Pat. No. 5,718,746, U.S. Pat. No. 5,747,562, U.S. Pat.No. 5,749,950, U.S. Pat. No. 5,803,959, U.S. Pat. No. 5,837,045, U.S.Pat. No. 5,846,307, U.S. Pat. No. 5,851,280, U.S. Pat. No. 5,861,447,U.S. Pat. No. 5,885,335, U.S. Pat. No. 5,895,522, U.S. Pat. No.5,922,118, U.S. Pat. No. 5,928,419, U.S. Pat. No. 5,976,233, U.S. Pat.No. 6,057,384, U.S. Pat. No. 6,099,632, U.S. Pat. No. 6,123,759, U.S.Pat. No. 6,153,001, U.S. Pat. No. 6,221,141, U.S. Pat. No. 6,221,142,U.S. Pat. No. 6,221,143, U.S. Pat. No. 6,281,267, U.S. Pat. No.6,329,446, US2001/0035110, EP-A-1114851, EP-A-1158030, WO01/10963,WO01/25340 and WO01/94476.

Titanium dioxide is also an example of a pigment that can be used, andis potentially advantageous because it is white in color. Titaniumdioxide can be difficult to disperse in an ink vehicle that iscompatible with an ink jet printer system. Those dispersions and/or inkvehicles that provide inkjet stable titanium dioxide can be used withthe nonionic latex polymer and multivalent cation pretreated textile.

In a preferred embodiment, a combination of a graft and block copolymersare used as co-dispersants for the titanium dioxide pigment, such asdescribed in U.S. application Ser. No. 10/872,856 (filed Jun. 21, 2004),the disclosure of which is incorporated by reference herein for allpurposes as if fully set forth. This combination of dispersants iseffective in stabilizing titanium dioxide pigment slurries and,furthermore, provides enhanced stability in the ink formulations. Otherpreferred titanium dioxide ink jet inks are described in commonly ownedU.S. Provisional Appln. Ser. No. 60/717,438 (filed Sep. 15, 2005), thedisclosure of which is incorporated by reference herein for all purposesas if fully set forth.

The white ink can be used in an ink set as a process color.Alternatively, it can be used as an underlayer to the colored image.When used in the underlayer scheme, the colored inks are printed within60 minutes of printing the white ink to optimize the colored image onthe textile. The use of white ink followed by colored inks isparticularly useful with colored textiles.

Additives

Other ingredients (additives) may be formulated into the inkjet ink, tothe extent that such other ingredients do not interfere with thestability and jetability of the finished ink, which may be readilydetermined by routine experimentation. Such other ingredients are in ageneral sense well known in the art.

Commonly, surfactants are added to the ink to adjust surface tension andwetting properties. Suitable surfactants include ethoxylated acetylenediols (e.g. Surfynols® series from Air Products), ethoxylated primary(e.g. Neodol® series from Shell and Tomadol® series from Tomah Products)and secondary (e.g. Tergitol® series from Union Carbide) alcohols,sulfosuccinates (e.g. Aerosol® series from Cytec), organosilicones (e.g.Silwet® series from GE Silicons) and fluoro surfactants (e.g. Zonyl®series from DuPont). Surfactants are typically used in the amount ofabout 0.01 to about 5% and preferably about 0.2 to about 2%, based onthe total weight of the ink.

Polymers may be added to the ink to improve durability. The polymers canbe soluble in the vehicle or dispersed (e.g. “emulsion polymer” or“latex”), and can be ionic or nonionic. Useful classes of polymersinclude acrylics, styrene-acrylics and polyurethanes. A particularlyuseful preferred binder additive is a crosslinked polyurethane asdescribed in US20050182154, the disclosure of which is incorporated byreference herein for all purposes as if fully set forth.

Biocides may be used to inhibit growth of microorganisms. Buffers may beused to maintain pH. Buffers include, for example,tris(hydroxymethyl)-aminomethane (“Trizma” or “Tris”).

Inclusion of sequestering (or chelating) agents such asethylenediaminetetraacetic acid (EDTA), iminodiacetic acid (IDA),ethylenediamine-di(o-hydroxyphenylacetic acid) (EDDHA), nitrilotriaceticacid (NTA), dihydroxyethylglycine (DHEG),trans-1,2-cyclohexanediaminetetraacetic acid (CyDTA),dethylenetriamine-N,N,N′,N″,N″-pentaacetic acid (DTPA), andglycoletherdiamine-N,N,N′,N′-tetraacetic acid (GEDTA), and saltsthereof, may be advantageous, for example, to eliminate deleteriouseffects of heavy metal impurities.

The components described above can be combined to make an ink in variousproportions and combinations in order to achieve desired ink properties,as generally described above, and as generally recognized by those ofordinary skill in the art. Some experimentation may be necessary tooptimize inks for a particular end use, but such optimization isgenerally within the ordinary skill in the art.

The amount of vehicle in an ink is typically in the range of about 70%to about 99.8%, and more typically about 80% to about 99%. Colorant isgenerally present in amounts up to about 10%. If a white ink is used,the white pigment can be up 25% in concentration. Percentages are weightpercent of the total weight of ink.

Other ingredients (additives), when present, generally comprise lessthan about 15% by weight, based on the total weight of the ink.Surfactants, when added, are generally in the range of about 0.2 toabout 3% by weight based on the total weight of the ink. Polymers can beadded as needed, but will generally be less than about 15% by weightbased on the total weight of the ink.

Drop velocity, separation length of the droplets, drop size and streamstability are greatly affected by the surface tension and the viscosityof the ink. Ink jet inks typically have a surface tension in the rangeof about 20 dyne/cm to about 70 dyne/cm at 25° C. Viscosity can be ashigh as 30 cP at 25° C., but is typically somewhat lower. The ink hasphysical properties are adjusted to the ejecting conditions andprinthead design. The inks should have excellent storage stability forlong periods so as not clog to a significant extent in an ink jetapparatus. Further, the ink should not corrode parts of the ink jetprinting device it comes in contact with, and it should be essentiallyodorless and non-toxic. Preferred pH for the ink is in the range of fromabout 6.5 to about 8.

Ink Sets

The term “ink set” refers to all the individual inks or other fluids aninkjet printer is equipped to jet.

In one preferred embodiment, the ink set comprises at least twodifferently colored pigmented inkjet inks, and optionally one may be awhite pigmented inkjet ink as described above.

In another preferred embodiment, the ink set comprises at least threedifferently colored pigmented inkjet inks, wherein at least one is acyan pigmented inkjet ink, at least one is a magenta pigmented inkjetink, and at least one is a yellow pigmented inkjet ink.

In addition to the colored inkjet inks just mentioned, it is alsopreferable to include a black pigmented inkjet ink in the ink set.

In addition to the CMYKW inks mentioned above, the ink sets may containadditional differently colored inks, as well as different strengthversions of the CMYKW and other inks.

For example, the inks sets of the present invention can comprisefull-strength versions of one or more of the inks in the ink set, aswell as “light” versions thereof.

Additional colors for the inkjet ink set may include, for example,orange, violet, green, red and/or blue.

Printing Method

The present method relates to digitally printing a pretreated textilesubstrate. Typically, this involves the following steps:

(1) providing an inkjet printer that is responsive to digital datasignals;

(2) loading the printer with the textile substrate to be printed, inthis case the pretreated textile substrate;

(3) loading the printer with the above-mentioned inks or inkjet inksets; and

(4) printing onto the substrate using the inkjet ink or inkjet ink setin response to the digital data signals.

Printing can be accomplished by any inkjet printer equipped for handlingand printing fabric. Commercial printers include, for example, theDuPont™ Artistri™ 3210 and 2020 printers, and the Mimaki TX series ofprinters.

As indicated above, a variety of inks and ink sets are available for usewith these printers. Commercially available ink sets include, forexample, DuPont™ Artistri™ P700 and P5000 series inks.

The amount of ink laid down on the fabric can vary by printer model, byprint mode (resolution) within a given printer and by the percentcoverage need to achieve a given color. The combined effect of all theseconsiderations is grams of ink per unit area of fabric for each color.In one embodiment, ink coverage is preferably from about 5 to about 17grams of ink per square meter of fabric for colored inks (includingblack and white inks).

If, however, a white ink is used as a background for the digitallyprinted image, up to about twelve times more white ink (generally fromabout 5 to about 200 grams of ink per square meter of fabric) may beused to obtain an enhanced final image. In such case, the white ink isinitially printed onto the substrate in at least a portion of the areato be covered by the final image (the underprint portion), then thefinal image is printed at least over the underprint portion.

The white ink can also be printed outside the boundaries of the finalimage (either as part of the initial background printing or subsequentlyas part of the image printing), for example, to generate a small,imperceptible boundary to the image, making the image appear to have adistinct boundary.

The use of the white ink for printing a background for an image isparticularly useful when printed onto colored (non-white) textiles.

Post Treatment of Fabric

Fabric printed with colored inks will typically be post-treatedaccording to procedures well-known in the textile printing art.

The printed textiles may optionally be post processed with heat and/orpressure, such as disclosed in US20030160851 (the disclosure of which isincorporated by reference herein for all purposes as if fully setforth). Upper temperature is dictated by the tolerance of the particulartextile being printed. Lower temperature is determined by the amount ofheat needed to achieve the desired level of durability. Generally,fusion temperatures will be at least about 80° C. and preferably atleast about 140° C., more preferably at least about 160° C. and mostpreferably at least about 180° C.

Fusion pressures required to achieve improved durability can be verymodest. Thus, pressures can be about 3 psig, preferably at least about 5psig, more preferrable at least about 8 psig and most preferably atleast about 10 psig. Fusion pressures of about 30 psi and above seem toprovide no additional benefit to durability, but such pressures are notexcluded.

The duration of fusion (amount of time the printed textile is underpressure at the desired temperature) is not believed to be particularlycritical. Most of the time in the fusion operation generally involvesbringing the print up to the desired temperature. Once the print isfully up to temperature, the time under pressure can be brief (seconds).

EXAMPLES Preparation of Nonionic Latex Polymers

The following ingredients and abbreviations were used to describe thechemical components of the nonionic latex polymers

DBTL=dibutyltindilaurate DMPA=dimethylol propionic acid EDA=ethylenediamine IPDI=isophoronediisocyanate TEA=triethylamineTETA=triethylenetetramine LHT=polypropylene glycol triol, from Bayer andDesmophen C 1200—a polyester carbonate diol from Bayer (Pittsburgh, Pa.)MPEG500—Methyoxypolyethlene glycol from Dow Chemical (Midland, Mich.)Tegomer D-3403—Polyether diol from Tego Chemie (Essen Germany) Synthesisof Polyether Diol with Polyethylene Glycol Side Chain.

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line was added 400 g MPEG500from Dow Chemical, 160.8 g (0.72) mole IPDI and 3 drops DBTDL. Themixture was reacted at room temperature until NCO was 5.4% or less. 476g LHT-240, polypropylene triol from Bayer and 10 drops DBTDL was addedto the flask. Then the solution was heated to 70° C. and held between 65and 70° C. until NCO % reached 0%. This polyether diol was calledPDiol-1.

Preparation of Nonionic Latex Polymer, a Polyurethane, Inv Ex 1.

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 150.5 gDesmophen C 1200, a 2000MW polycarbonate/ester diol, 180 g PDiol-1, 100g acetone and 0.03 g DBTL. The contents were heated to 40° C. and mixedwell. 72 g IPDI was then added to the flask via the addition funnel at40° C. over 60 min, with any residual IPDI being rinsed from theaddition funnel into the flask with 10 g acetone.

The flask temperature was raised to 50° C., then held at 50° C. untilNCO % was less than 2.03%.

700 g deionized (Dl) water at 50° C. was added over 10 minutes, followedby 24.4 g EDA 75 g TETA (as a 6.25% solution in water) over 5 minutes,via the addition funnel, which was then rinsed with 40.0 g water. Themixture was held at 50° C. for 1 hr, then cooled to room temperature.

Acetone (−310.0 g) was removed under vacuum, leaving a final dispersionof polyurethane with about 35.0% solids by weight and pH around 7.5.This polymer has 17 wt % or 0.39 meq. ethylene oxide unit.

Preparation of Nonionic Latex Polymer, a Polyurethane, Inv Ex 2.

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 200 g DesmophenC 1200, 150 g PDiol-1, 123 g acetone and 0.03 g DBTL. The contents wereheated to 40° C. and mixed well. 80 g IPDI was then added to the flaskvia the addition funnel at 40° C. over 60 min, with any residual IPDIbeing rinsed from the addition funnel into the flask with 10 g acetone.

The flask temperature was raised to 50° C., then held for 30 minutes. 10g DMPA followed by 7.5 g TEA was added to the flask via the additionfunnel, which was then rinsed with 10 g acetone. The flask temperaturewas then raised again to 50° C. and held at 50° C. until NCO % was lessthan 1.25%. 740 g deionized (DI) water at 50*C was added over 10minutes, followed by 46.3 g EDA (as a 6.25% solution in water) over 5minutes, via the addition funnel, which was then rinsed with 40.0 gwater. The mixture was held at 50° C. for 1 hr, then cooled to roomtemperature.

Acetone was removed under vacuum, leaving a final dispersion ofpolyurethane with about 35.0% solids by weight and pH around 7.5. Thispolymer has 13 wt % or 0.30 meq. ethylene oxide unit and 0.017 meq. COOHgroup.

Preparation of Nonionic Latex Polymer, a Polyurethane, Inv Ex 3

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 265 g DesmopheneC 1200, 50 g Tegomer D3403, a polyether diol from Tego Chemie, 110 gacetone and 0.03 g DBTL. The contents were heated to 40° C. and mixedwell. 75 g IPDI was then added to the flask via the addition funnel at40° C. over 60 min, with any residual IPDI being rinsed from theaddition funnel into the flask with 10 g acetone.

The flask temperature was raised to 50° C., then held for 30 minutes. 10g DMPA followed by 7.5 g TEA was added to the flask via the additionfunnel, which was then rinsed with 10 g acetone. The flask temperaturewas then raised again to 50° C. and held at 50° C. until NCO % was lessthan 1.47%. 654 g deionized (DI) water at 50° C. was added over 10minutes, followed by 59.2 g TETA (as a 6.25% solution in water) over 5minutes, via the addition funnel, which was then rinsed with 40.0 gwater. The mixture was held at 50° C. for 1 hr, then cooled to roomtemperature.

Acetone was removed under vacuum, leaving a final dispersion ofpolyurethane with about 35.0% solids by weight pH around 7.5. Thispolymer has 11.3 wt % or 0.26 meq. ethylene oxide unit and 0.019 meq.COOH group.

Preparation of a Comparative Nonionic Latex Polymer, a Polyurethane,Comp Prep Ex 1

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 235 g DesmophenC 1200, 80 g PDiol-1, 112 g acetone and 0.03 g DBTL. The contents wereheated to 40° C. and mixed well. 82 g IPDI was then added to the flaskvia the addition funnel at 40° C. over 60 min, with any residual IPDIbeing rinsed from the addition funnel into the flask with 10 g acetone.

The flask temperature was raised to 50° C., then held for 30 minutes. 15g DMPA followed by 10 g TEA was added to the flask via the additionfunnel, which was then rinsed with 10 g acetone. The flask temperaturewas then raised again to 50° C. and held at 50° C. until NCO % was lessthan 3.2%.

687 g deionized (DI) water at 50° C. was added over 10 minutes, followedby 46.3 g EDA (as a 6.25% solution in water) over 5 minutes, via theaddition funnel, which was then rinsed with 40.0 g water. The mixturewas held at 50° C. for 1 hr, then cooled to room temperature.

Acetone was removed under vacuum, leaving a final dispersion ofpolyurethane with about 35.0% solids by weight and pH around 7.5. Thispolymer has 7.4 wt % or 0.17 meq. ethylene oxide unit and 0.026 meq.COOH group.

Preparation of a Comparative Nonionic Latex Polymer, a Polyurethane,Comp Prep Ex 2

This polymer has 3.9 wt % or 0.09 meq. ethylene oxide unit and 0.042meq. COOH group.

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 330 g DesmopheneC 1200, 55 g PDiol-1, 112 g acetone and 0.03 g DBTL. The contents wereheated to 40° C. and mixed well. 120 g IPDI was then added to the flaskvia the addition funnel at 40° C. over 60 min, with any residual IPDIbeing rinsed from the addition funnel into the flask with 10 g acetone.

The flask temperature was raised to 50° C., then held for 30 minutes. 30g DMPA followed by 20 g TEA was added to the flask via the additionfunnel, which was then rinsed with 10 g acetone. The flask temperaturewas then raised again to 50° C. and held at 50° C. until NCO % was lessthan 4.3%.

900 g deionized (DI) water at 50° C. was added over 10 minutes, followedby 62.1 g EDA (as a 6.25% solution in water) over 5 minutes, via theaddition funnel, which was then rinsed with 40.0 g water. The mixturewas held at 50° C. for 1 hr, then cooled to room temperature.

Acetone was removed under vacuum, leaving a final dispersion ofpolyurethane with about 35.0% solids by weight pH around 7.5. Thispolymer has 3.9 wt % or 0.09 meq. ethylene oxide unit and 0.042 meq.COOH group.

Preparation of a Comparative Latex Polymer, a Polyurethane, Comp Prep Ex3

To a dry, alkali- and acid-free flask, equipped with an addition funnel,a condenser, stirrer and a nitrogen gas line, was added 699.2 gDesmophen C 1200, 280.0 g acetone and 0.06 g DBTL. The contents wereheated to 40° C. and mixed well. 189.14 g IPDI was then added to theflask via the addition funnel at 40° C. over 60 min, with any residualIPDI being rinsed from the addition funnel into the flask with 15.5 gacetone.

The flask temperature was raised to 50° C., then held for 30 minutes.44.57 g DMPA followed by 25.2 g TEA was added to the flask via theaddition funnel, which was then rinsed with 15.5 g acetone. The flasktemperature was then raised again to 50° C. and held at 50° C. until NCO% was less than 1.23%. This polymer has 0.036 meq. COOH group and nononionic components.

Testing

The Inventive Examples and Comparative Examples were tested forstability with a multivalent cationic salt solution. An amount of latexpolymer to obtain 10 wt % in the final aqueous solution/emulsion was putinto a beaker, the mixture stirred, then a 15 wt % calcium nitrateaqueous solution was added over about 5 minutes The dry polymer and thecalcium nitrate tetrahydrate weight ratio was 10/15. The mixture wasstirred for an additional 5 minutes. After 10 minutes and 24 hours, thesolution/emulsion was observed for coagulation, gelling or other signsof instability. If no coagulation was observed, it is rated compatibleor stable. If the test solution was coagulated after 10 minutes or 24hours, the combination of latex polymer and calcium nitrate testsolution is judged to be not an inventive combination.

TABLE 1 Stability Test for Nonionic Latex Polymers with MultivalentCationic Solution Inv Comp Comp Comp Ex 1 Inv Ex 2 Inv Ex 3 Ex 1 Ex 2 Ex3 Stability Com- Com- Com- Coag- Coag- Coag- with patible patiblepatible ulated ulated ulated Calcium nitrate Nonionic 0.39 0.30 0.260.17 0.09 0 EO meq. Anionic 0 0.017 0.019 0.026 0.042 0.036 acid meq.

Printing Conditions

The examples described below were done using an Epson 3000 ink jetprinter, a Fast T-Jet™ from US Screen Printing Institute (Tempe, Ariz.),the and prints were made on various substrates. The textile substratesused were 419 100% cotton and 7409 65/35 polyester/cotton blend fromTestfabrics Hanes Beefy T 100% cotton t-shirts, Hanes Heavy weight 100%cotton t-shirts, Hanes 50/50 polycotton cotton t-shirts, and a blackfabric from Joann's Fabric (woven 100% cotton tweed). All test printswere fused at about 170° C. for about 1 minute.

Pigmented Inks were used for testing the nonionic latex polymer andmultivalent cation pretreatment solution and comparison pretreatmentformulations. The inks used were DuPont™ Artistri™ P700 and P5000 seriesinks. The white ink used was described in IJ0132 and IJ0196.

Colorimetric measurements were done using a Minolta SpectrophotometerCM-3600d using Spectra Match software.

Where indicated the printed textile was tested for washfastnessaccording to methods developed by the American Association of TextileChemists and Colorists, (MTCC), Research Triangle Park, N.C. The AATCCTest Method 61-1996, “Colorfastness to Laundering, Home and Commercial:Accelerated”, was used. In that test, colorfastness is described as “theresistance of a material to change in any of its color characteristics,to transfer of its colorant(s) to adjacent materials or both as a resultof the exposure of the material to any environment that might beencountered during the processing, testing, storage or use of thematerial.” Tests 2A and 3A were done and the color washfastness andstain rating were recorded. The ratings for these tests are from 1-5with 5 being the best result, that is, little or no loss of color andlittle or no transfer of color to another material, respectively. Crockmeasurements were made using methodology described in AATCC Test Method8-1996.

Pretreatment Solutions

Reagent grade calcium nitrate tetrahydrate (Aldrich) was mixed withdeionized water until the calcium nitrate was completely in solution.Six pretreatment solutions were prepared, and a comparative solutionwith only a multivalent cation present was also prepared.

TABLE 2 Pretreatment Solutions 1–6 Component (Wt %) as Calcium NitrateTetrahydrate as Calcium Nitrate Pretreatment Solution 1; 15 10.45Nonionic Latex Polymer Inv Ex 1 Pretreatment Solution 2; 15 10.45Nonionic Latex Polymer Inv Ex 2 Pretreatment Solution 3; 15 10.45Nonionic Latex Polymer Inv Ex 3 Pretreatment Solution 4* 15 10.45Pretreatment Solution 5** 15 10.45 Pretreatment Solution 6*** 15 10.45Comparative Pretreatment 10 6.95 Solution 1 *Pretreatment Solution 4contains 10% by weight (solids)of Printrite ™ 2003, a nonionic polymer.**Pretreatment Solution 5 contains 10% by weight (solids) of Airflex ™4530. ***Pretreatment Solution 6 contains 10% by weight (solids) ofPermax ™ 200.

Print Testing of Pretreatment

Print Test Set A: A 419 white cotton was printed with DuPont™ Artistri™P5000 CMYK Inks with various pretreatment conditions. Each example waspretreated by spraying the textile in an area about the same as theintended image to be printed, dried and printed with the Epson 3000printer. The estimated amount of calcium nitrate hydrate on the T-shirtprior to printing was about 7.5 grams/square meter. 5 grams of nonioniclatex polymer. Then the printed textile was fused at 170° C. for 1minute. The printed textile were tested for optical density, 2A and 3Awash fastness and wet and dry crock. Table 3 shows the results of thisprinting.

TABLE 3 Print Testing of Pretreatment Conditions Set A Treatment ColorOD 2A 3A Dry Wet No pretreat Black 1.13 4.4 3.7 4.6 1.9 PretreatmentSolution 1 Black 1.24 ND 1.5 3.8 1.1 Pretreatment Solution 3 Black 1.25ND 1.8 3.5 1.4 Pretreatment Solution 4 Black 1.24 ND 1.8 2.9 1.5Pretreatment Solution 5 Black 1.37 3.9 2.5 4.7 1.3 Pretreatment Solution6 Black 1.35 ND 2.2 4 1 Comparison Black 1.23 ND 0.5 2.1 1.3Pretreatment Solution No pretreat Cyan 1.09 3.6 2.8 4.0 2.1 PretreatmentSolution 4 Cyan 1.12 2.2 4.7 1.2 Pretreatment Solution 5 Cyan 1.17 4.43.3 4.6 1.6 No pretreat Magenta 1.02 4.5 4.2 4.3 2.6 PretreatmentSolution 5 Magenta 1.16 4.6 3.8 4.6 2.1 No pretreat Yellow 1.12 4.8 4.33.0 2.1 Pretreatment Solution 5 Yellow 1.31 4.8 3.9 3.5 1.7 ND notdetermined

Each pretreatment inventive example shows an improvement in opticaldensity (OD), over the non pretreated sample and an improvedwashfastness and crock over the Comparison Pretreatment Solutionexample.

Print Test Set B: A 7409 polyester/cotton blend was printed with DuPont™Artistri™ P5000 CMYK Inks with various pretreatment conditions. Eachexample was pretreated by spraying the textile in an area about the sameas the intended image to be printed, dried and printed with the Epson3000 printer. The estimated amount of calcium nitrate hydrate on theT-shirt prior to printing was about 7.5 grams/square meter. 5 grams ofnonionic latex polymer. Then the printed textile was fused at 170° C.for 1 minute. The printed textile were tested for optical density, 2Aand 3A wash fastness and wet and dry crock. Table 4 shows the results ofthis printing.

TABLE 4 Print testing of Pretreatment Conditions Set B Treatment ColorOD 2A 3A Dry Wet No pretreat Black 0.96 3.3 2.5 4.7 2.1 PretreatmentSolution 5 Black 1.30 2.3 1.2 4.6 1.1 Pretreatment Solution 4 Black 1.272.6 ND 4.0 1.2 Pretreatment Solution 3 Black 1.27 1.8 ND 4.2 1.2Comparison Pretreatment Black 1.26 1 ND 4.2 1 Solution No pretreat Cyan0.95 2.7 2.1 4.0 2.4 Pretreatment Solution 5 Cyan 0.99 3.0 2 4.4 1.8 Nopretreat Magenta 0.85 3.1 2.3 4.6 3.0 Pretreatment Solution 5 Magenta1.09 4.7 2.2 4.6 2.0 No pretreat Yellow 0.96 4.1 3.6 3.3 2.8Pretreatment Solution 5 Yellow 1.27 3.7 1.7 3.0 1.9

Each pretreatment inventive example shows an improvement in opticaldensity (OD), over the non pretreated sample and an improvedwashfastness and crock over the Comparison Pretreatment Solutionexample.

Print Test Set C: The test shows the use of a white ink used after theinventive pretreatment, but prior to the image printing. A black t shirtwas printed with DuPont® Artistri® P5000 CMY inks. Pretreatment Solution# 4 was used for all of the white ink tests

TABLE 9 Printing on Black T Shirt: Inventive Example Set 7 D65/10° Max.L* a* b* C* h° OD K/S Cyan Pretreated White C 48.27 16.89 29.94 34.37240.56 1.16 6.28 ink Black T-shirt Magenta Pretreated White M 39.0737.62 10.56 39.07 344.32 1.26 8.17 ink Black T-shirt Yellow PretreatedWhite Y 66.27 −2.86 63.64 63.70 92.58 1.40 11.49 ink Black T-shirtunprinted Std Black T-Shirt 16.91 −0.59 −0.55 0.81 223.09 1.71 24.39T-Shirt Comp No Pretreatment C 18.35 −1.80 −5.88 6.15 253.02 1.69 23.28Example White ink black Cyan T-shirt Comp No Pretreatment M 18.92 4.74−3.67 6.00 322.30 1.62 19.93 Example White ink black Magenta T-shirtComp No Pretreatment Y 21.89 −3.40 4.75 5.84 125.58 1.59 18.62 ExampleWhite ink black Yellow T-shirtThe inventive examples have significantly improved Chroma and L*relative to the comparative examples.

1. A method of digitally printing a textile comprising the steps of: (a)pretreating the textile with an aqueous pretreatment solution comprisinga nonionic latex polymer and a multivalent cationic salt solution, (b)drying the pretreated textile, (c) digitally printing the dried,pretreated textile with a colored ink jet ink, whether the nonioniclatex polymer has sufficient nonionic components such that the nonioniclatex polymer is stable in the presence of the multivalent cationic saltsolution.
 2. The method of claim 1 where the nonionic latex polymercomprises one or more nonionic components selected from the group ofethylene oxide derivatives, acrylamide, hydroxyethyl, vinylpyrrolidone,and ethyleneimine.
 3. The method of claim 1 where the nonionic latexpolymer comprises one or more polymer components selected from the groupof urethanes, vinylacetates, ethylene-vinylacetates, acrylates,acylamides, styrenes, and styrene-acrylate polymers.
 4. The method ofclaim 3 wherein the polymer component of the nonionic latex polymer isselected from the group urethanes, acrylates, and acylamides.
 5. Themethod of claim 4 where the polyurethane has a nonionic componentderived from ethylene oxide components.
 6. The method of claim 5 wherethe ethylene oxide components are at least 15 milliequivalents/gram ofnonionic latex polymer.
 7. The method of claim 1, wherein themultivalent cation is selected from one or more of the group ofmultivalent cations of elements Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr, V,Cr, Mn, Fe, Ru, Co, Rh, Ni, Pd, Pt, Cu, Au, Zn, Al, Ga, In, Sb, Bi, Ge,Sn and Pb.
 8. The method of claim 1, wherein the multivalent cation iscalcium.
 9. The method of claim 8, wherein the pretreatment solutioncomprises a solution of a multivalent cationic salt in water, whereinthe multivalent cationic salt is selected from the group consisting ofcalcium nitrate, calcium nitrate hydrate, calcium chloride, calciumhydrate and mixtures thereof.
 10. The method of claim 1, wherein thetextile is pretreated with the pretreatment solution in a wet pick-up offrom about 0.20 to about 7.5 grams of multivalent cationic salt per 100grams of fabric.
 11. The method of claim 1, wherein the textile isprinted with a colored inkjet ink set comprises at least two differentlycolored inkjet inks.
 12. The method of claim 11 where the colored inkjetink is a pigmented ink.
 13. The method of claim 11, wherein at least oneof the pigmented inkjet inks is white.
 14. The method of claim 12,wherein the ink set comprises at least three differently coloredpigmented inkjet inks, wherein at least one is a cyan pigmented inkjetink, at least one is a magenta pigmented inkjet ink, and at least one isa yellow pigmented inkjet ink.
 15. The method of claim 14, wherein theink set further comprises a black pigmented inkjet ink.
 16. The methodof claim 14 or 15, wherein the textile is printed with the at least twodifferently colored inkjet ink to an ink coverage of between about 5 toabout 17 grams of ink per square meter of fabric.
 17. The method claim14 or 15, wherein the pigmented inkjet ink comprises, or each thepigmented inkjet inks in the inkjet set individually comprise, ananionically stabilized pigment in an aqueous vehicle.
 18. The method ofclaim 1, further comprising the step of post-treating the printedtextile with heat and/or pressure.
 19. The pretreated textile of claim1, wherein the fabric comprises a cotton or cotton blend.
 20. Thepretreated textile of claim 1 which, subsequent to application of thetextile pretreatment solution, has been dried to equilibrium moisture atambient temperature.